With each node generation, the ongoing miniaturization and component densification of semiconductive devices presents new challenges to the semiconductor manufacturing industry. One challenge occurs where chlorohydrocarbon, such as trans 1,2-dichloroethylene, is used to form oxide films over a semiconductive substrate. The chlorine disassociated from a chlorohydrocarbon is often used to form an oxide liner within an isolation trench. The chlorine promotes corner rounding at the upper edges of the trench and also functions as a getter for contaminants during the oxide liner's formation. The corner rounding is beneficial because it helps prevent structural thinning at the upper corners of trench, which reduces the risk of structural breakdown when subjected to operating voltages.
Typically, the chlorohydrocarbon along with a carrier nitrogen gas is first introduced into a heating chamber that is operated at temperatures of around 900° C. before it is passed into the deposition chamber. Problems arise however, because substantial disassociation is not presently achieved in the heating chamber. This requires the deposition chamber to be operated at temperatures at least as high as the heating chamber (e.g. 900° C.) to achieve the complete disassociation of the chlorine from the hydrocarbon. Further problems are encountered due to the fact that the high operating temperature within the deposition chamber makes oxidation growth difficult to control.
Because the process temperatures within both the heating and deposition chambers are equally high, the growth rate of the silicon oxide film is hard to control and thicknesses less than about 7.0 nm to about 8.0 nm are, therefore, very difficult to achieve. Lowering the operating temperature within the deposition chamber is not a viable option because the higher temperatures of 800° C. or more must be used in the deposition chamber to complete the disassociation of the chlorine from the hydrocarbon and prevent the incorporation of the carbon into the oxide film. Furthermore, increasing the dimensions of the trenches so that the thickness of the oxide liner does not close off the trench or produce a trench that is too narrow to receive high density plasma or other material is also not a viable option since critical dimensions of all semiconductive components, including trench size, is continually shrinking.
Accordingly, what is needed in the art is a semiconductive device and method of manufacturing that device that provides for the continued use of these chlorohydrocarbons without the detriments associated with the above-discussed conventional processes.